physics solvers

A physics solver is the most honest collaborator I have: it doesn't care what I intended, only what I actually built. I set the goals, collision, pressure, an anchor, a load, and let it settle until the geometry stops arguing with itself. The good ones feel less like running a tool and more like negotiating with a material that has read the manual. Which raises the obvious problem: it read the manual I wrote.

Fig. 5 · Solver convergence. Residual falls steeply, then flattens; the marked point is where the geometry stops changing.